On 2020-03-18 06:20, Jiaxun Yang wrote:
This controller appeared on Loongson-3 family of chips to receive
interrupts
from PCH PIC.
It is a I8259 with optimized interrupt polling flow. We can poll
interrupt number
from HT vector directly but still have to follow standard I8259
routines to mask,
unmask and EOI.
Co-developed-by: Huacai Chen <chenhc@xxxxxxxxxx>
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
v4-v5:
Enhancements according to maz's suggestions:
- Add static for private struct
- Drop pointless rename
- Fix DT parse bug
- Clarifications in comments and commit message
---
arch/mips/include/asm/i8259.h | 1 +
drivers/irqchip/Kconfig | 10 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-loongson-htpic.c | 149 +++++++++++++++++++++++++++
4 files changed, 161 insertions(+)
create mode 100644 drivers/irqchip/irq-loongson-htpic.c
[...]
+int __init htpic_of_init(struct device_node *node, struct device_node
*parent)
+{
+ unsigned int parent_irq[4];
+ int i, err;
+ int num_parents = 0;
+
+ if (htpic) {
+ pr_err("loongson-htpic: Only one HTPIC is allowed in the system\n");
+ return -ENODEV;
+ }
+
+ htpic = kzalloc(sizeof(*htpic), GFP_KERNEL);
+ if (!htpic) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ htpic->base = of_iomap(node, 0);
+ if (!htpic->base) {
+ err = -ENODEV;
+ goto out_free;
+ }
+
+ htpic->domain = __init_i8259_irqs(node);
+ if (!htpic->domain) {
+ pr_err("loongson-htpic: Failed to initialize i8259 IRQs\n");
+ err = -ENOMEM;
+ goto out_iounmap;
+ }
+
+ /* Interrupt may come from any of the 4 interrupt line */
+ for (i = 0; i < HTPIC_MAX_PARENT_IRQ; i++) {
+ parent_irq[i] = irq_of_parse_and_map(node, i);
+ if (parent_irq[i] < 0)
irq_of_parse_and_map() returns 0 when there is no interrupt to be
mapped. You should probably test for that too.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
